1. Field of the Invention
The present invention relates to a production system of electrolyzed water in which fresh water such as city service water supplied under pressure is electrolyzed to produce electrolyzed water (alkaline water and acidic water).
2. Description of the Prior Art
Disclosed in Japanese Patent Laid-open Publication Nos. 7-251177 and 9-192666 is a production system of electrolyzed water of the type in which electrolyzed water is produced in an electrolyzer when a faucet provided on an outlet end of a discharge conduit is opened to discharge the electrolyzed water therethrough. As in the production system of electrolyzed water, there is not provided any washing means for the discharge conduit, the passage of the discharge conduit particularly for alkaline water becomes narrow due to scale adhered and deposited therein in use of a long period of time. It is, therefore, difficult to discharge the alkaline water in a good condition for a long period of time.
To solve the above problem, the present invention was made to provide a production system of electrolyzed water which includes an electrolyzer of the flow-down type having positive and negative electrodes respectively provided in a pair of electrode chambers subdivided by a partition membrane, a pair of inlet conduits connected to the electrode chambers of the electrolyzer for supplying treatment water into the electrode chambers, a pair of outlet conduits connected to the electrode chambers for discharging alkaline water and acid water produced in the electrode chambers, a pair of discharge conduits each provided with a faucet at their outlet ends, a flow passage changeover valve disposed between the outlet conduits and discharge conduits for switching over the flow passage of alkaline water and acid water discharged from the outlet conduits, a pair of drain conduits respectively bifurcated from the discharge conduits between the changeover valve and the faucets, a pair of drain valves provided on the drain conduits, a pair of flow quantify sensors provided on the inlet conduits for detecting a quantity of the treatment water flowing therethrough, control means for applying an electric power to the electrodes in response to a detection signal applied from the flow quantity sensors when at least one of the faucets on the discharge conduits was opened and opening the drain valve on the drain conduit bifurcated from the discharge conduit the faucet of which is closed, the control means being further arranged to switch over the polarity of the electrodes and the position of the changeover valve in a set condition and to switch over only the position of the changeover valve or the polarity of the electrodes in a specific condition, detection means for detecting clog in the discharge conduits when a quantity of treatment water detected by the flow quantity sensors is less than a predetermined quantity, and indication means for indicating the clog in the discharge conduits detected by the detection means.
When the faucet on either one of the discharge conduits is opened in the production system of electrolyzed water, a quantity of water flowing through the inlet conduit is detected by either one of the flow quantity sensors. In response to a detection signal from the flow quantity sensor, the electrodes are supplied with an electric power under control of the control means, and the drain valve on the drain conduit in connection to the discharge conduit closed at its faucet is opened. Thus, alkaline water and acid water are produced by electrolysis of the water supplied into the electrode chambers of the electrolyzer and discharged into the discharge conduits through the outlet conduits and changeover valve.
In operation of the production system of electrolyzed water, the polarity of the electrodes and the position of the changeover valve 50 are switched over under control of the control means in a set condition, and only the position of the changeover valve 50 or the polarity of the electrodes is switched over under control of the control means in a specifica condition. Accordingly, in a condition where the polarity of the electrodes and the position of the changeover valve are switched over at the same time, alkaline water is discharged through either one of the discharge conduits, while acid water discharged through the other discharge conduit. As a result, an amount of scale is deposited in the discharge conduit through which the alkaline water is continuously discharged. However, when only the position of the changeover valve or the polarity of the electrodes is switched over, the acid water is discharged through the discharge conduit through which the alkaline water was discharged before the position of the changeover valve or the polarity of the electrodes is switched over, while the alkaline water is discharged through the discharge conduit through which the acid water was discharged before the position of the changeover valve or the polarity of the electrodes is switched over. As a result, the scale deposited in the discharge conduits is dissolved and washed by the acid water after the position of the changeover valve or the polarity of the electrodes was switched over. This is useful to eliminate the scale deposited in the discharge conduits thereby to maintain the passage of the discharge conduits in a good condition. It is, therefore, apparent that if each discharge place of the alkaline water and acid water is changed from one of the discharge conduits to the other discharge conduit or vice versa, the alkaline water and acid water can be discharged in a good condition for a long period of time.
In addition, when the flow quantity of water detected by the flow quantity sensors is less than a predetermined quantity, a clog caused by the scale deposited in the discharge conduits, drain conduits and drain valves is detected by the detection means, and the indication means is activated to inform the user of the clog in the conduits and drain valve.
In a practical embodiment of the present invention the indication means may be replaced with alarm means for informing a user of the clog in the discharge conduits detected by the detection means. In addition, the production system of electrolyzed water may be further provided with means for prohibiting activation of the indication means or the alarm means until the production time of electrolyzed water becomes a predetermined time after only the position of the changeover valve or the polarity of the electrodes was switched over. In such a case, it is able to prevent useless activation of the indication means or the alarm means.
Furthermore, the indication means is replaced with a switchover means for switching over only the position of the changeover valve or the polarity of the electrodes when the clog in the discharge conduits is detected by the detection means. There is also provided a means for prohibiting activation of the switchover means until the production time of electrolyzed water becomes a predetermined time after the position of the changeover valve or the polarity of the electrodes is switched over. The alkaline water is discharged alternately through the discharge conduits at each time when the clog in the discharge conduits is detected. Thus, the scale deposited in the discharge conduits, drain conduits and drain valves can be automatically removed. This facilitates the maintenance management of the production system of electrolyzed water. In addition, as the activation of the switchover means is prohibited until the production time of electrolyzed water becomes the predetermined time after the position of the changeover valve or the polarity of the electrodes is switched over, useless operation of the switchover means can be avoided. In such a case, it is preferable that indication means for informing the user of the kind of electrolyzed water are provided adjacent the faucets on the discharge conduits. For example, a blue lamp may be provided adjacent the faucets capable of discharging the alkaline water, while a red lamp may be provided adjacent the faucets capable of discharging the acid water.